Process of manufacturing gas for lighting or heating purposes from bituminous fuels



C. W. IBOTSFOFID.

PROCESS OF MANUFACTURING GAS FOR LIGHTING OR HEATING PURPOSES FROM BITUMINOUS FUELS. APPLICATION FILEDAIUNF. I3| I919.

1,385,167, amed July 19,1921.

2 SHEETS-SHEET I- I zzvenfor M ax M V 0. wt sd'rsmm PROCESS OFMANUFACTURJNG GAS FOR LIGHTING 0R HEATINGPURPOSES FROM BH'UMINOUS FUELS" -APPL|CATiON FILEDJU,NE'I3,191 9.

Patented July 19, 1921.

2 SHEETS-SHEET 2- UNITED STATES PATENT OFFl-CEQ CLAUDE'WINFIELD BOTSFORD, F LOS ANGELES, CALIFORNIA.

rnocnss or MANUFACTURING T 0 all whom it" may concern:

Be it known that I, CLAUDE VINFIELD Borsronn, a citizen of Los Angeles, in the county of Los Angelesand State of California,'ha've invented new and useful improvements in the processes of manufacturing gas for lighting or heating purposes from bituminous fuels by an intermittent process, of which the following is a specification.

---This invention relates to a process for the manufacture of gas from bituminous fuels or fuels containing volatile combustible matter, according to the usual water-gas or carburetted water-gas method (consisting in I5 blasting a bed of ignited fuel air to incandescence and then passing steam through the fuel, thereby generating water-gas which may be carbureted in checker chambers known as carburetor and superheater) but with a new method of recovering and utilizing the excess combustible blast gas which is produced in large quantities when bituminous fuels are used in the generator, and which has hitherto retarded the general use of such fuels in water-gas manufacture.

The objects of this invention are:

(1). To utilize more efficiently bituminous fuels and similar fuels as water-gas generator fuel.

(2). To maintain a more uniform and high temperature in the generator fuel.

(3). To increase the gas making capacity of a given size water-gas set.

(4). To maintain perfect control of the temperatures in the checker chambers.

(5). To conserve oil (carbureting oil) by making a better grade of blue gas (watergas) which requires less oil for its carburation.

(6). To eliminate the smoke nuisance which usuallyaccompanies the use of bituminous fuels as generator fuel.

(7 To avoid the difiiculties caused by caking, matting and arching of the fuel which are encounteredwhen coking bituminous coals are used in the generator with the present methods of operating.

(8). To avoid the excessive deposit of carbon in the checker chambers, which is the cause of considerable trouble when using GAS FOR LIGHTING OR HEATING PURPOSES FROM BITUMINOUS FUELS.

Specification of Letters Patent. Patented July 19 1921 Application filed June 13,

1919. Serial No. 303,830.

bituminous fuel in the generator according to prevailingmethods of operating.

(9). To avoid clinker difficulties, or reduce them to a minimum.

H'eretofore in the manufacture of carbureted water-gas the practice has been to blast the ignited generator fuel until it is sufiiciently hot for the production of watergas, meanwhile burning part of the blast gas generated, in the checker chambers but permitting the excess combustible gas to pass out the stack as waste gas. )Vith coke fuel and when making a high standard gasone of 600 B; t. u. and over-practically all of the blast gas generated is required for heating the checker chambers, but when bituminous fuels or mixed fuels containing afuel with volatile combustible matter are substituted for coke, the quantity of combustible gas wasted at the stack as blast gas is a very appreciable amount.

I have found, on blasting coal fuel, that the individual lumps carbonize or coke on the outside, and in this course downward in the generator the lumps are not completely carbonized until more than eight or ten runs are made. Thus the surface heating of the fuel results in the blast gas being as richin CO as when the fuel mass is at a uniformly high temperature since the reaction CO +C:2C() is dependent'on high temperature and contact time. for completion. A larger volume and a richer, blast gas is produced when operating with bituminous coals and blasting them to a uniform hi h temperature for making gas, than is obtained when coke or other high carbon fuel is used. The volatile matter of the bituminous fuel also adds to the quality and quantity of the combustible blast gas.

I have also found that when operating with any particular bituminous fuel that there is produced a definite quantity of blast gas in excessof the quantity required to heat the checker chambers and that this excess is the greatest for those fuels containing the highest percentage of volatile combustible matter. Also the quantity of this excess blast gas available per 1,000 cu. ft. of gas made is greater when making low standard purposes.

gas than when making a high standard gas,

other things being equal. As the standard is decreased from 600 B. t. u. the quantity availabl increases. This excess combustible blast gas I utilize in my process.

In Figure 1 is shown a complete unit for making gas by my process consisting of the usual generator. carburetor, superheater and connections and equipped also with special valve connections which are not a part of the carbureted water-gas sets in common use but which are a help in accomplishing my In Fig. 2 these special partsare shown separately, and consist in valves which operate in unison and pipe connections thereto whereby the gas may be conducted direct to the holder from the generator, by-passin'g the checker chambers. The means whereby the valves are operated in unison is not material to this application for Letters Paten.t. In Fig. 2 A, O and E are pipe connections through which gas passes, the. direction being controlled by valves B and D operated in unison by a mechanism shown as a rack and pinion F, and control wheel G. In Fig. 1 H is the generator containing the fuel, I and J are checker chambers known as carbureter and superheater respectively. K is the generator ofi'-take valve for blast gas and for water-gas during up runs, while L is the valve through which the down run watergas passes from the generator. M and N are steam lines to the generator for making down and up runs; the respective control valves are shown at U and T. O is the secondary air line to the carbureter and P is the oil inlet for injecting carbureting oil. Q is the gas off-take from the superheater and R is the stack cap which is opened only to let the stack gas-waste blast gas-out ofthe set. S is the off-take from the seal or wash box W and leads to a gas holder or other suitable receiver. V is the generator air blast line.

The operation of the set is carried out as follows: The ignited fuel in generator H is blasted with air or other oxygen carrying gas through line V while valves K and B and stack cap R are open, and valves L and I) are closed. The blast gas produced passes through K, A, B and '0 into the carbureter I thence to superheater J and out at R. Secondary air (or oxygen) is meanwhile supplied to the carbureter through 0 in amountssutficient for the complete combustion otthe combustible matter in the blast gas generated. This blasting of both generator and carbureter is continued until the checker chambers are sufliciently hot for carbureting purposes; at this point the cap R is closed, the air through 0 turned cit and the generator blast is continued until the generator fuel is sufliciently hot for making good water gas. The blast gas generated during this last period passes out through Q. W, and S to the holder. The blast at V is now discontinued and steam is injected into the fuel bed from beneath, at N, by opening valve T. The steam combines with the hot carbon chiefly by the reaction.C+H O:CO+I'I producing water gas. This gas traverses the same course to the holder, namely through K. .v. H. C. I J. Q, iv, and S. and is carbureted in its course by the injection of carbureting oil into carbureter at I After the fuel in the generator has reached a certain relatively low temperature the steam is turned oil and the: cycles are repeated except that during the run down-steam is used. that is. the steam valve U is opened instead of T and the steam enters the generator at M. The valves are changed tor this run as follows:

L and B are open and I: and D are closed.

The series of cycles are now repeated. the relative number ot up and down runs nadc depend on the condition of the fuel bed. It can be seen that in this operation the tarry matter in the blast gas during the second stage of blasting will have a tendency to carboniZe on the checker brick. particularly during the second stage of blasting when no air is admitted at U. and result in a shorter active life of the checker bricks. I have found that in some cases it is essential to avoid this particularly when using a heavv viscous or tarry oil as alrburcting oil and when the generator fuel is rich in tarry matter. Ilnder these conditions the brick work becomes carboned rapidly. and to avoid this I take the blast as produced during the second stage of blasting direct trom the generator to the holder. by-passing the checker chambers. I have found that it is also necessary to take. the gas oil in this manner in order to obtain the maximum capacity from the set since the volume of blast gas generated during the second stage of blasting is greater per unit oi time when the resistance offered by the checker brick not encountered; this is particularly true when the air is supplied by the commonly preferred tan type blower. A complete cycle taking the gas off in this manner is as tollows: The generator fuel is blasted with air or oxygen through V at Fig. l. valve K and .B and cap'R- being open and valve D and I;

neously closed and cap It is closed. The

generator blast is continued until the gen eratortucl is as hot as desired meanwhile taking the blast gas now produced oil through K. it. D and F. to the holder. Jitter the generator fuel is suiliciently hot the scribed. After the fuel in the generator hasreached a relatively low temperature the steam is turned off and the cycle is repeated. Up and down runs are made as described when required. The carbureting oil may be admitted during the second stage of blast ing, inwhich case all the blast gases pass through the checker chambers. This I find is very desirable when using heavy, viscous, high boilingoils which are only completely cracked with difficulty, for it allows a longer time of contact, a longer input period and, a

decreased concentration of oil vapors and I am aware, in that it is a three stage process, and that the richest portion of the blast gas generated is utilized as a part of the finished gas. The change in composition of the blast gas as the blasting progresses, when using a high volatile bituminous coal (such as Illinois bituminous coal) I have found to be as follows:

Last 5 minute of blasting.

First minute of blasting.

Per cent. by vol Per cent. by vol 18. 0

The complete cycle in-this case was: 311; minutes total blasting and 4: minutes steam run, The amount of increase of hydrogen and methane during the blasting varies somewhat depending on the quantity of steam used during the run, on the moisture in the fuel used and on the volatile constituents of the fuel. With any particular fuel,

I have found, the percentage of CO, H and UH; are the highest in the blast gas recovered. whenthe moisture in the fuel is the highest and when the steam used per 1,000 cu. ft. of finished gas made is the lowest,

It is not possible to specify a definite length of the second'stage of blasting, the period when the blast gas is conducted to the holder, since with coking coals it is necessary to make a longer blast than with noncoking coals in order to prevent the. caking and arching of the fuel in the upper part of the generator fuel mass. Also when a low standard gas is desired, lower than the average prevailing city standards, a longer blast is made into the holder. In ordinary operation and when making gas from 500 B. t. u.

to 565 B. t. u. per cu. ft. the average length 7 of this period is seldom shorter than twenty seconds nor longer'than fifty seconds. A typical cycle is as follows:

First stage, 3 minute blast, taking gasoif through superheater stack.

Second stage, 5, minute blast, generator generator fuel is thoroughly heated, in order to prevent the combustion of the blast gas at the stack. In such cases the temperature in the fuel mass is not high enough for a suiiicient length of time to allow the clinlrer to flow and collect on the grates, instead. it collects on the generator wall, This second period of blasting permits the operator to eliminate the side wall clinlrer difficulties.

The water gas and carbureting processes are not new and l do not claim them as my own.

I claim.

1. A process for the manufacture of car bureted gas using bituminous coal or other ll fl fuel containing volatile matter as generator fuel in three stages consisting in, first, blasting the ignited fuel contained in a generator with an oxygencontaining gas, burning the blast gas so generated to complete combustion in suitable carbureting chambers by supplyingoxygen to them; then, when these lllll chambers are sufficiently hot, shutting off their oxygen supply and blasting the gen; erator fuel until it is suiliciently hot for gas making purposes conducting the blast gas new generated into a holder; and third,

lflli shutting an the generator blast and injecting steam into the fuell bed for the purpose of steam distilling the fuel and simultaneously.

making water-gas, carbureting the thus produced. and conducting it to the holder containing the recovered blast gas where it is mixed with. the latter in proportions as generated, substantially as described.

2. A process for the manufacture of carburetecl gas using bituminous coals or other fuels containing volatile matter as generator fuel, in three stages, consisting in, first, blasting the ignited fuel contained in a generator with an oxygen containing gas, burn ing the gas so generated to complete combustion in suitable 'carbureting chambers by supplying oxygen to them until they are suiiiciently hot for carbureting purposes; then, second, turning off the oxygen supply to these chambers and blasting the generator fuel until it is sufliciently hot for gas lllfl llli making purposes, conducting the gas nowproduced into the holder for carbureted gas but by a separate route than through the cal-bursting chambers for the purposes of decreasing the back pressure and decreasing where both gases are mixed in rn-oportione m the carbon deposit on the checker brick; and as generated, substantially as described.

"third shutting off generator blast and in- In testimony whereof ll ufiis: my signature jecting steam into the fuel bed for the purin the presence of two Witnesses.

pose of steam distilling the fuel and simul- CLAUDE TINFIEI D BONWFOPD taneously making water-gas, conducting the M J gas thus produced through the carbureting Witnesses:

chambers, wherein it is carbureted, and into BENJ. F. J. 010mm,, the holder containing the recovered blast gas HELEN EROMAN. 

